The present invention relates to an elevator landing door structure.
Traditionally, the landing doors of an elevator are mounted by attaching both the upper and lower ends of the door frame directly to the building. In other words, the door sill is fixed to the lower edge of the door opening while the overhead supporter is fixed separately to the upper edge of the door opening. A drawback with such a structure is above all the difficulty of installation and structural complexity. Both the door sill and the overhead supporter must be installed separately according to accurate measurements.
Previously known are also solutions in which the landing door is fixed to a secondary structure attached to the building. For instance, in elevator shafts of steel construction, landing doors have been mounted using an H-shaped steel frame generally attached by its lower end to the floor slab and by its upper end to the slab supporting the floor above. Such a frame requires a great deal of design work and is expensive to manufacture and difficult to install.
In general, mounting the landing door is a problematic and difficult task because it is difficult to find suitable attachment points for both the door sill and the overhead supporter and because the shaft dimensions may vary considerably from floor to floor. Nevertheless, the door openings must be precisely aligned along the same straight line. Moreover, the landing door structures cannot be rigidly connected to each other between different floors because the elevator shaft undergoes longitudinal motion to which the elevator structures must adapt themselves.
The object of the invention is to eliminate the drawbacks referred to above. A specific object of the invention is to disclose a new type of elevator landing door structure that is as simple as possible as well as cheap to manufacture and install.
The landing door structure of the invention comprises a door sill attached to the lower edge of the landing door opening, an overhead supporter and at least one door panel movable along and supported by the overhead supporter. According to the invention, vertical frames are fixed to the door sill after it has been mounted in place on the floor, on either side of the door opening, and the overhead supporter is mounted on the vertical frames. In other words, the vertical frames are rigidly mounted and supported by the door sill. Moreover, the vertical frames are fixed by their upper parts via junctures that are rigid in a horizontal plane but at the same time flexible or yielding in the vertical direction so that the effects of possible vertical movements of the shaft structure are freely transmitted via the junctures holding the upper part of the vertical frames.
The vertical frame is preferably attached by its upper part to another corresponding vertical frame which is mounted at the edge of the door opening on the next floor above and fixed to the door sill on that floor. This fixture is so implemented that the vertical frames, disposed substantially one above the other as vertical extensions of each other, are rigidly connected to each other in the horizontal plane but the juncture between them permits sliding or yielding in the longitudinal direction of the vertical frames as necessary due to thermal expansion and other movements occurring in the structures of the elevator shaft.
The length of the vertical frame is preferably so designed that it comprises an upper extension extending above the point of attachment of the overhead supporter, the vertical frame being fixed by said extension via a juncture rigid in the horizontal plane. Similarly, the vertical frame preferably extends below the point of attachment of the door sill so that the part of the vertical frame below the door sill forms a lower extension to which the upper end of the vertical frame at the edge of the door opening on the floor below can be attached.
The vertical frames vertically aligned with each other on different floors and forming extensions of each other can be connected to each other in a variety of ways. The essential point is only that the junctures ensure that the vertical frames are held rigidly in position in a horizontal plane while allowing vertical movements of the vertical frames in relation to each other. Thus, the juncture may consist of a suitable sleeve surrounding the vertical frames or a suitable clamp connection in which the vertical frames are locked between two elements pressed towards each other. Another essential point is that the vertical frames are not directly butted on each other; instead, a suitable gap is left between the vertical frames at the juncture. The vertical frame may be made of various types of rigid profile steel, such as U channel section, H section, T section or round or cornered tubular profile steel.
It is also possible within the scope of the inventive idea to fasten the vertical frame by its upper part directly to the door sill fixed to the lower edge of the door opening on the floor above. In this case, too, the juncture is implemented as a structure that is rigid in the horizontal plane but capable of yielding appropriately in the vertical direction.
Especially in the case of an elevator door structure for the topmost floor and also in applications where the floor-to-floor distances are particularly large, the upper part of the vertical frame can be fastened directly to the shaft wall. In this embodiment, too, the juncture is so implemented that it is rigid in the horizontal plane but capable of yielding appropriately in the vertical direction.
The vertical frame is preferably attached to the end of the door sill. Likewise, the overhead supporter is preferably attached by its ends between the two vertical frames, although, depending on the installation space and the profile of the vertical frame used, other ways of implementing the attachment are possible.
The elevator landing door structure of the invention provides significant advantages as compared with prior art. The door structure is very simple and easy to erect. After the door sills have been fitted in the landing door openings of the elevator shaft and fixed in place, no further accurate measurements are needed. The vertical frames are provided with precise attachment points, e.g. perforations, both for the door sill and the overhead supporter. Thus, the vertical frames are fixed to the ends of the door sill and the overhead supporter is fixed to the upper ends of the vertical frames. At the same time, the upper ends of the vertical frames are connected to a corresponding vertical frame fixed to the door sill on the floor above.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.